Could we detect and intercept RAMA with today's tech?

[flynn]

I believe he now lives in Sri Lanka. <div class="Discussion_UserSignature"> <font color="#800080">"All God does is watch us and kill us when we get boring. We must never, ever be boring" - <strong>Chuck Palahniuk</strong>.</font> </div>

 

[yevaud]

Yes. Columbo, and he's a Professor Emeritus at the University there, as I recall. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[nyarlathotep]

>"When the Borg reach Mars, the defence system activates. Never mind that Mars may have been on the other side of the Sun."<br /><br />No problem. In the 24th century we can just move Mars. Reverse the polarity on the whatchamacallit and 'compensate' or somesuch.

 

[docm]

Mars basing is no problem when you have warp-capable quantum torpedos <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> </div>

 

[halman]

docm,<br /><br />Any problem can be solved with the correct application of the right amount of energy. We just are having problems with the 'correct' and 'right amount' parts. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[willpittenger]

Forget that. The Borg ship was in sight of Mars. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[alokmohan]

What is borg ship?

 

[docm]

You kidding? Oh well....<br /><br />In the Star Trek universe a 3 km/side cubic starship occupied by an aggressive race of cy<b>borg</b>s called the Borg;<br /><br />Borg: http://en.wikipedia.org/wiki/Borg_(fictional_aliens)<br /><br />Cube ship: http://en.wikipedia.org/wiki/Borg_starship<br /><br />They were the subject of many, many story lines including the movie Star Trek: First Contact<br /> <br />IMO if we aren't careful with our use of bionics/biotech/nanotech we'll end up like them; mindless drones who are slaves to their attached technologies. <div class="Discussion_UserSignature"> </div>

 

[halman]

docm,<br /><br />It has already started. Notice the people wearing their cellphones?<br /><br />Resistance is futile! <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[alokmohan]

Cyborgs.Dangereous thing.Oh Clark,what have you wrought.Oh Rama save your disciples from borg.As you know we are notoriously peaceful.Borgs may land in Pakistan.

 

[halman]

alokmohan,<br /><br />I don't think that Clarke had anything to do with the concept of the Borg. He did, however conceive of artificial intelligence, and the HAL 9000 of 2001: A Space Odyssey is still an excellent example of what computer designers and AI researchers are striving for.<br /><br />Seeing as this thread is about detecting hazardous objects in space, I would like to pitch the idea of creating some kind of system for detecting asteroids which orbit the sun inside the orbit of Earth. These are probably the greatest threat right now, as observing them from Earth is basically impossible.<br /><br />By building satellites which could detect reflections from bodies down to 10 meters in diameter, and placing them in orbit around the Sun at the distance that Venus is, we could develop a cataloge of objects which might threaten the Earth in a year or so. By using triangulation between two of these satellites, we could precisely locate such objects, and calculate their orbits. The detectors might not necessarily work in the visible light spectrum, using instead infared, so that they would not be confused by more distant objects.<br /><br />There seems to be a bias toward thinking that only objects from the outer reaches of the Solar System could be a threat to Earth, due to their velocity relative to the Earth's. But even an object overtaking the Earth would still have considerable kinetic energy after falling into the Earth's gravity well. We have detected at least two asteroids which have passed within 1 million kilometers of Earth before we knew that they were there. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[docm]

<blockquote><font class="small">In reply to:</font><hr /><p>It has already started. Notice the people wearing their cellphones?<br /><br />Resistance is futile! <p><hr /></p></p></blockquote><br /><br />It's even further along than that. Have you checked out DARPA's exoskeleton & Future Force Warrior stuff? Adaptive camo (practical invisibity), networked battlefield at the soldier level, heads up displays in the helmet, liquid & shear thickened armors etc. etc.<br /> <div class="Discussion_UserSignature"> </div>

 

[rocketman5000]

WEEE!!! Welcome to a "Brave New World"

 

[willpittenger]

Do you use Windows or MS Office? If so, you have been assimilated -- by Microsoft. In Dilbert cartoon strips, they represent MS as the Borg complete with cube ships. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[Boris_Badenov]

<font color="yellow"> I would like to pitch the idea of creating some kind of system for detecting asteroids which orbit the sun inside the orbit of Earth. These are probably the greatest threat right now, as observing them from Earth is basically impossible. </font><br /><br /> I have often wondered why radar is not used for this. Do you know? <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>

 

[yevaud]

Not powerful enough. To do so, we'd have to station Radar systems throughout the entire Solar System. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[Boris_Badenov]

The VLA & Arecibo both have used radar to study Solar System objects. If they are powerful enough to look at Titan, why is it they cannot be used to look for Sun side NEO's? <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>

 

[vogon13]

You have to know where the object is, allow for the light time delay, and be listening for the echo at the correct time.<br /><br />This gets very tricky for objects you don't already know about.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[yevaud]

Umm, neither is an active Radar system - they're both passive - highly sensitive receivers, in short. There's a very big difference between the two. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[willpittenger]

When I suggested that Cassini scan the depths of Jupiter or Saturn, problems that I was told would exist included that Cassini's Radar is not really a Radar (same for Magellan). It is actually a transmitter with some fancy programming and probably a lot of ground analysis of the returns to back Cassini up. MRO on the other hand, has a real radar. Also, neither craft has to wait long (about 2 seconds?) for the signal to return. For a NEAR, we are potentially talking about hours -- not seconds. In order to be listening at the appropiate time, you have to know roughly how far you are looking. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[yevaud]

Precisely. Also, for anything at distance, the signal strength grows quite weak, and then has to return as well. A very weak signal indeed, if we're talking an object at, say, a billion miles.<br /><br />I might add, in the case of the VLA and Arecibo, they are detecting objects that radiate. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[MeteorWayne]

I don't believe that's correct Yevaud.<br />According to what's here Both Arecibo and Goldstone have been used for Delay-Doppler measuremants of at least Totoutis. That is a standard radar send and receive, so the objects radiation was not needed.<br />These are of course, <b>huge</b> dishes that can transmit and receive a radar signal. I don't believe the VLA would be able to direct a large enough outgoing signal. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[yevaud]

Yes, but look at what it says (relevant portion bolded):<br /><br /><i>Delay-Doppler radar imaging during Toutatis's Dec. 1992 close approach <b>(to within 0.024 AU, or 9.4 lunar distances)</b> provided information that was unprecedented for an Earth-crossing object (Ostro et al. 1995). Hudson and Ostro (1995, hereafter HO95) used a comprehensive physical model to invert the lower-resolution images to estimate the asteroid's detailed shape and inertia tensor, initial conditions for the asteroid's spin and orientation, the radar scattering properties of the surface, and the delay-Doppler trajectory of the center of mass.</i><br /><br />That's relatively nearby, and is still possible. But the point was that at any real distance, it isn't possible, using Earth-based systems.<br /><br />If that weren't so, we would have performed Radar surveys of Luna, Mars, etc. from here, instead of having to launch missions. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[MeteorWayne]

I agree for sure. I was just saying that actual radar images had been made of some asteroids. You are correct in pointing out that they were in the 'hood.<br />Further out it is nigh near impossible for the reasons you described. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[halman]

Boris1961,<br /><br />All forms of radiation are affected by the inverse square law, which states that the strength of the radiation diminishes by the inverse square of the distance. This means that even powerful radars cannot detect objects very far away. To detect objects in the Solar System, we generally use the Sun as the transmitter of the signal, and look for a reflection of the signal. We see planets by the light of the sun reflected back at us. Objects which are between us and the sun will not reflect light to us, except at certain points in their orbits.<br /><br />Infared might be superior for the detection of objects in orbits close to the Sun because they will radiate very strongly in near infared, wheras objects more distant will not. Trying to detect objects using visible light means comparing starfields, looking for displacement over time. Dark objects, which have very low albedo values, are difficult to detect using the visible light spectrum. But any detector will have to be closer to the Sun than the Earth, so that it is looking outward, away from the Sun, not towards it. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>